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Trekkor
Is it dependant on venue? Alameda for example.

I want to run these mega-phone, trumpet, zoomie pipes I got from Martin Baker.

I know they will be LOUD. Will they boot me. ( make me muffler up )?

KT
Jeroen
megaphones give no back pressure so you'll prolly end up with very little low rpm torque
not good for AX...
Trekkor
But, I might like the sound... lol2.gif

KT
nebreitling
they'll be loud as shit. i should hope you'd be stopped from running, but GGR has seemed pretty relaxed about noise limits at the last few AX's. i think the limit at Alameda is 94db, but there were atleast 4 or 5 cars last AX well above that...


but i don't think they'll help you in an AX anyway sad.gif
nine14cats
Hi Trekkor,

The Alameda sound limit is supposed to be the same as Laguna Seca....92db. At Alameda I run my Laguna set up which makes the sound limit at the meter shack just after turn 5. All other Auto-x venues I was able to use my Phase 9's which would work out to ~98db on my 2.7 liter 6 with headers.

I think you will be too loud with the megaphones, although there were several cars this year that sounded too loud.

Bill P.
Trekkor
I might put 'em on Thurs night and buzz around the back roads scuffin' the Yok's. Playin' race cars ohmy.gif

KT
McMark
Come by here and see if I'm home. I wanna hear.
Randal
QUOTE]i think the limit at Alameda is 94db[/QUOTE]

That is the limit, but it's not scientifically enforced. The way it works - if anyone complains about a car then the AX chairman let's that driver know there is a problem – and expects it corrected before the next event.

BTW if the sound level was measures/enforced uniformally amongst all runners, then there would be lots of people changing mufflers between events.

As to the next question, who are the biggest complainers, you’ll have to guess.
Trekkor
Mark, If I come by you'll hear me come across Silverado Trail. lol2.gif

Randal, I'm thinking, 911 guys?

So, if I show up all loud and obnoxious, do I pack the Bursch in case someone doesn't like the vroom, vroom?

Trek
Randal
Nope, not the 911 guys.

Although my calculated guess is that most of the offenders do drive 911's.

Did I tell you Trekkor that I heard a 911 with 40 series flowmasters and that it sounded great, but not loud?
Trekkor
I like a loud race car.

So, maybe the people who bring their sleeping babies with them are grumpy.

Oh, BTW, Randal, I'll be down at HPH in the morning for the alignment and....I'll surprise you!

Trek
Randal
Mr. T.

Give me a call in the morning and maybe I pop up for lunch.

Maybe Brad will be available as well?
nine14cats
Randal and Trekkor,

What time for lunch? laugh.gif

Bill P.
Britain Smith
I would be in for lunch also...let me know what time.

-Britain
Demick
This weekend is at Candlestick. Noise shouldn't be a problem there. Alameda is where excessive noise is a problem.

There was a guy at the WCC with a nitrous 914. He had some straight pipes similar to the megaphones you want to put on. I was surprised that the car was not nearly as loud as I expected.

Demick
Mueller
QUOTE
But, I might like sound.....


the sound you hear while [b]in the car/b] is loud obnoxious noise to people outside of the vehicle smile.gif

I also see no reason to try and "test" the sound limits just 'cause you think your car will sound cool or that you "want" to get the car blackflagged for being loud....maybe it's just me, but i'd be embarrassed getting dinged for having an exhaust that i knew from jump street was just put on so that I get noticed while driving out there on the course... smash.gif

I'm not trying to be ass, but I think this boarders on being inconsiderate to your fellow racers......

now if you are putting on an exhuast that you know will give you XXhp and you need that edge, that is different in my opinion...(off my soapbox )


beerchug.gif
Britain Smith
QUOTE(Demick @ Oct 25 2004, 10:02 PM)
This weekend is at Candlestick. Noise shouldn't be a problem there. Alameda is where excessive noise is a problem.

There was a guy at the WCC with a nitrous 914. He had some straight pipes similar to the megaphones you want to put on. I was surprised that the car was not nearly as loud as I expected.

Demick

It wasn't that loud to you but you weren't driving behind it and sniffing the fumes!!!

-Britain
McMark
Okay, if it's going to be a big lunch gathering, maybe I can bum a ride with Trekkor and join in. What time's your appointment Kairos?
Trekkor
Mike, thanks.

maybe I should reconsider. idea.gif

Good points.

I'm not a showboater, never have been.
I like the sound of loud motors, always have.

I love the sound of a stinger in a covered parking garage or tunnel.

I had a VW crew cab with a 2110cc and stinger, loved it.

KT
Mueller
QUOTE
It wasn't that loud to you but you weren't driving behind it and sniffing the fumes!!!


not to diss him, but when he left Laguna Seca, my wife and I watched him go up a small hill, as his car got louder and louder my wife asked why the car was getting louder, but not going any faster going up the hill???

the proportion of sound to speed was not very even smile.gif

Trekkor, at least give them a try, maybe they wont be as bad as we are making them out to be wink.gif
Randal
QUOTE
What time for lunch?


Usually 11:45am is a good time to show up.

QUOTE

maybe it's just me, but i'd be embarrassed getting dinged for having an exhaust that i knew from jump street was just put on so that I get noticed while driving out there on the course...  


How would you feel if the reason for the loud exhaust was horsepower?
ChrisFoley
Those megaphones will hurt the power, maybe even worse than your Bursch.
You also run the risk of burning a piston if you don't re-tune the engine.
A single megaphone on a 4-1 header would be a much better idea.
If you want to hear them I suggest you put them on, rev up the engine in the driveway, and then throw them in the scrap pile. rolleyes.gif
rhodyguy
the guy with megaphones and nitrous wasn't loud??? on the freeway you could hear him 1/2 mile ahead of you when he got on it. i don't think the juice was activated either. i wonder if the engine still runs?

kevin
i love porsche
whats the deal with having to re-tune the engine for the megaphones?

would megaphones be good for trackdays? (im thinkin pocono) any suggestions racer chris?
ChrisFoley
QUOTE(i love porsche @ Oct 26 2004, 09:52 AM)
whats the deal with having to re-tune the engine for the megaphones?

would megaphones be good for trackdays? (im thinkin pocono) any suggestions racer chris?

If the engine is tuned for a muffler that has backpressure the megaphones will lean out the engine significantly.

Since the exhaust pulses on each side of the engine are only 90 degrees out of phase you get no help as far as scavenging goes with that style of tailpipe, so a 4-1 header is a much better choice. A megaphone setup on a 4-1, properly tuned, would work fine at the track.
In fact I have a used European racing header that came with a megaphone. The collector was shot though, so I plan to make a new collector and sell the system.
Trekkor
I put them on ohmy.gif

Running up throught he gears on the backroad was amazng, though. Maybe I'll drag race tommorrow night at Sears.

Don't know if I even dare leave them on. unsure.gif

KT
McMark
I could hear you forever. I stood out there and listened to you shift.
Series9
I think loud is fun, especially for racing. Hell, even my 'street' mufflers are probably over the legal limit (what ever that is in NM).

I bet if you take it to the drags like that, no one will complain, but then they are drag racers... biggrin.gif
Joe Bob
QUOTE(trekkor @ Oct 25 2004, 07:55 PM)
I might put 'em on Thurs night and buzz around the back roads scuffin' the Yok's. Playin' race cars ohmy.gif

KT

Dude....proper tools fer proper fools......


Read the rules, bring a DbA meter and quieter muffs....trust me ...BTDT got the freaking tee shirt to prove it.....

Got my ass booted at San Diego one day....whipped out MY meter....showed that were all wet. They were using DbC rating that showed I was over the limit...bullshit....the rules said Db fucking AAAAAAAAAAAAAA

Didn't make a whole lotta friends but I made my point and I don't live down there.....made my runs and qualified for the HI AX championship for 1999.....

BTW....if ya wanna borrow my meter....just ask.
Trekkor
Why bother, Mikey, didn't you hear me from there? rocking nana.gif

KT kowabunga!
Joe Bob
Woof!!!!
Trekkor
QUOTE(markd@mac.com @ Oct 26 2004, 07:02 PM)
I could hear you forever. I stood out there and listened to you shift.



Good! biggrin.gif

I feel sorry for all the people above me in the parking garage. I bet they thought the thing was coming down. lol2.gif

I had to baby it down 3rd street so the kids wouldn't cry w00t.gif

It's my evil twin.

KT
Trekkor
I'll video some drive-by's tommorow so I can judge the sound levels.

KT
Brad Roberts
The reason they nailed Randal... he likes to fry the tires from the start so he revs it up... everyone else is out on a Sunday drive....

I have yet to see ANY PCA autoX where a sound meter was in use...



B
Trekkor
I've run the car for for two seperate sessions, rather...ahem, hard. unsure.gif

The inside of the trumpets are black ( running rich ).
I must have the fuel pressure set high already.

I'm leaving them on. I'll change out during break to compare the performance.

Only 4 runs of deafening chaos. cool_shades.gif

KT
Trekkor
Shot some video today. Not really that loud.
The cars at the vintage racing at Sears a few weeks back were louder.

KT
d914
Roebling rd allows 104db, I can't run megs. My buddy got pulled at 107db on a small six. Plus they mainly help towards red line.
Trekkor
zoomba
Trekkor
I ran the megaphones all day with no complaints.
Some people actually enjoyed it biggrin.gif

It added to the fun for me. biggrin.gif

No noticable power loss or gain.

Good fun... Long course. 1:22 for me.

KT
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